Effective Use of Divisional Application in Japan

Unlike the US practice, we do not have a system of continuation applications. Instead, as a similar practice, we can file divisional applications. 

When a client wishes to continue prosecution, for example, after receiving a Decision of Rejection, we recommend filing a divisional application, because of the following advantages:

  • The claim amendments which may be filed together with an Appeal are strictly restricted to amendments for the following purposes only: (i) cancelling one or more claims; (ii) restricting the scope of claims by limiting one or more features already recited in the pending claims; (iii) correcting any error in claim recitations; and (iv) clarifying any ambiguous word or expression in the claims as pointed out in the Decision of Rejection.  Adding a new element to the claims, removing a currently existing element from the claims, broadening or changing the gist of the claims, and increasing the number of claims are impermissible.  On the other hand, in the case of filing a divisional application, the claims may be drafted freely as far as each claim has sufficient supports in the specification and drawings.
  • When the option of filing an Appeal is chosen, the application may be finally rejected with no chance of receiving another Office Action, if the Board of Appeals judges the ground for rejection in the Decision as not having been overcome.  On the other hand, when the option of filing a divisional application is chosen, there would be at least one more chance of receiving an Office Action, even if the Examiner judges the ground for rejection in the Decision as not having been overcome.

Meanwhile, after receipt of a Decision to Grant, a divisional application may be filed tentatively with the same claim set as the allowed one, and a preliminary amendment may be filed later to amend the claims.  The preliminary amendment may be filed at any time before examination of the divisional application starts, but it is recommended to file it together with a request for examination for the divisional application.  The request for examination is due in 30 days after the actual filing date of the divisional application.

Together with the preliminary amendment, it is also required under the current Japanese patent practice to submit a Written Statement to explain that each (amended) claim of the divisional application (i) has sufficient support in the disclosure and (ii) is free from any of the grounds for rejection notified during examination of the parent application.

1) When divisional application can be filed in Japan?

  • Anytime when amendments can be filed
  • Within 4 months after receipt of Decision of Rejection
  • Within 30 days after receipt of Decision to Grant (Notice of Allowance)

The Japanese patent law regarding divisional applications was revised in 2007, and under the current rule, it is possible to file divisional applications within 30 days of the receipt of a Notice of Allowance or a Decision to Rejection.

Meanwhile, please note that there is a case that a divisional application cannot be filed when you receive a Decision to Grant. If a Decision of Rejection was once issued before the issuance of the Decision to Grant, a divisional application cannot be filed at the time of the issuance of a Decision to Grant for the reason that there was an opportunity to file a divisional application when a Decision of Rejection was issued.

2) Requirements for divisional application:

  • Claims of divisional applications must not be substantially the same as the claims rejected in parent applications
  • Disclosures of the divisional applications shall be within the scope of the original disclosures of parent applications
  • Disclosures of divisional applications further shall be within the scope of the disclosure of the parent applications immediately before the division

3) First Office Action against a divisional might be deemed to be a Final:

Please be informed that a first Office Action is deemed to be a final Office Action if the reasons of rejection raised in the Office Action(s) issued during the examination of the parent application are not overcome in the divisional application.  That is, if the claims and/or the specification of the divisional application have the reason(s) of rejection that was(were) already raised during the prosecution of the parent application, a first Office Action in the divisional application will be made final.  Hence, if possible, we propose to draft claims in the divisional application in such a manner so to ensure that all the reasons of rejection raised in the parent application are overcome.

4) Benefit of obtaining the earlier filing date:

If the claims of a divisional application are identical to the claims of its parent application, the divisional application is not entitled to retroactively claim the filing date of its parent application as an effective filing date, and accordingly, the divisional application will naturally be rejected over the publication of its parent application as lacking novelty.